The overall goal of this project is to determine the clinical and cellular/molecular effects of PDT using Pc 4 on stage 1A-2A CTCL/MF. CTCL is a rare cutaneous malignancy with a prevalence of less than 200,000. It is hypothesized that topically applied Pc 4 followed by red light is a saf and tolerable treatment for early stage CTCL/MF. The aim is to demonstrate both clinical safety and tissue biological effects using skin biopsies of Pc 4-PDT treated versus untreated control lesions. These biopsies will be analyzed at the gene and protein expression level to determine potential biomarkers of response to PDT in CTCL, that can be used to optimize future protocols for Phase 2 and 3 clinical trials. The known photostability of Pc 4 will be utilized by evaluating the benefits of repeated photoexposures. This will be aided by an in vivo imaging device that measures Pc 4 levels in real time in skin lesions through fluorescence spectroscopy.